Generator



Nov. 27, 1923.

A. E. BUCHENBERG GENERATOR Original Filed July 14. 1917 @www/Coz ,4W/)7 gache/merg Patented Nov. 27, 1923.

UNITED" STATES ALVIN E. BUCHENBERG, F TOLEDO, OHIO.

GENERATOR. i

Application led July 14, 1917, Serial No. 180,672. Bene-wed April 17, 1923.

To whom t may 001mm:

Be it known that I, ALVIN E. BUCHEN-- BERG, a citizen of the United States, residing at Toledo, in the county of Lucas and State of Ohio, have invented certain new and useful Improvements in Generators, of which I declare the following to be a full, clear, and exact description. v

This invention relates to improvements in generators and particularly to automatic means for regulating the output of the generator.

In electric starting and lighting systems for automobiles, there is not as great a drain on the storage battery in warm weather or in a warm climate, as in cold weather or a cold climate, due to the factthat the engine starts more quickly and there is less use for the lighting system, moreover the ampere hour capacity of the battery is reduced with decrease in temperature. It is4 highly desirable to provide means for regulating the output of the generator so that this output will be decreased in warm weather, when there is less drain on the storage battery, and so that the generator will operate at its maximum output in the cool weather, when such maximum output is desirable.

An object of this invention is to provide 80 automatic means, controlled by atmospheric temperature for regulating the output of the generator. A further object of my invention is to provide temperatureresponsive means vfor adjusting the third brush of a generator provided with the third brush system of regulation. l

Further objects, and objects relating to economies of manufacture and details of construction, will definitel appear from the 40 detailed description to fo low.

I accomplish the objects of my invention by the devices and means descrlbed in the following specification. j

A structure constituting a preferred embodiment 4of my invention is illustrated in the accompanying drawing forming a part of this specification, in which:

Figure I is asectional view through the casing of a generator, show ing in end elevation a structure in which my invention is embodied. A

Figure II isa view in end elevation of a A'third brush ,equipped with Yautomatic con- `trolling means constructed in accordance u with my invention.

Vmounted. A curved bi-metallic strip 26 has Figure III is a plan view of the blank from which the bracket, in'which the third brush is mounted, is constructed.

Figure IV is an enlarged, detail, sectional view taken substantially on the line IV-IV of Figure II; and', Figure V is a view similar to Figure IV, but showing a slightly modified form of my invention.

In the drawings, similar reference numerals refer to similar parts throughout the several views, and the sectional views are taken looking in the direction of the arrows at the end of the section lines.

In accordance with the theory of the third brush system of regulation for generators the output of the generator may be decreased by movement of the third brush in a direction opposite to the direction of rotation of the armature, while the output may be increased by movement of the third brush in the direction of rotation of the armature. .According to my invention I provide a heatresponsive element, which is so mounted and connected with a movably mounted third brush, as to move the third brush relative to the armature whenever there is any increase in the temperature of the air surrounding-or within the generator.

The brush holder ring 12 is secured to the end wall 11 of the casing 10 by means of the bolts 13 passing vthrough the slots 14 in ears extending from saidfbrush holder ring, The fixed brushes 16 are mounted in the brush holder brackets 15, which are carried, by the ring 12, in the usual manner. They third brush is lmounted in a bracket comprising the U-shaped portion 17, with the ears 18 on each sidethereof, said bracket being adjustably secured to the ring" by means of the bolts 19, passing through said ears 18 and throu h the slot 20 in the brush holder ring. v The fIanges 21 are struck in from the sides of the part 17 and engage the brush 22 at opposite .sides so that the brush may rock upon the ed es of said flanges as a ulcrum, as appears rom Figure IV of the drawing. The tail 23v extends from one .of the ears 18 rearwardly and has, at its rear end, an upturned finger 24C,y in which the bolt 25 is one end thereof secured to and clamped between the nuts carrled on the bolt- 25. The

y opposite end of said bi-metallic lstrip is 1 mounted in the notch 27 formed in the side of the Q-shaped portion 17 of the bracket, so llo that the hee end on said strip engages the brush 22 at a point a slight distance removed trom the tulcrum thereof.

This strip is made oli two strips ot diderent metal Isecured together, said metals being suchthat they have diderent coemcients of expansion, such, tor instance, as brass and steelu its a result, any change in'temperature will result in a movement ot the curved strip, as indicated by dotted lines in lligure lii, The unequal coehcients oit expansion ot the curved strip cause it to straighten out and move out ot its normal curved position, so that, as the temperature increases, the curved bi-metallic strip 26 will tend to occupy the position shown in dotted lines in Figure lV, and the 4tree end thereot" will tend to push the brush 22 to one side, rocking it on its tulcrum on the edges oit the danges 2l, so as to move it relative to the armature. Fingers 28 and 29 are struck upwardly from the bracket and the hnger 28 is odset relative to the it er 29, and one end of the coiled spring 30 is mounted between the lingers 28 and 29, the other tree end et said spring 31 engagin the end ot the brush 22 so as to yielding y hold it inv engagement with the coutatpr and to tend to return it to its normal position when the bi-metallic strip is contracted to its normal position.

ll have shown, in Figure lll, a plan view oit the blank from which the bracket carrying the third brush is made, and the mannerin which the bracket is termed from this blank will be a parent from the inspection otithe view without further description, it being apparent that the blank 'is slit where indicated by full lines, and is creased or iolded where indicated by dotted lines.

lin Figure V li have shown a modification oi my invention, in which theibrush 22 is mounted between the dan es 3d, struck inwardly trom the sides'yoi t e lll-shaped portion 32 ot the braclret which,as in the other torni oil my invention, is secured to the brush holder ring by the 'bolts l2. ll. bimetallic strip has onegend thereof bent laterally and secured to the side ot the [Ll-shaped portion 32 oit the bracket while the other end isi-secured 'to the tree end ot lever 38 having a head 39, which engages the end or the brush 22. The bracket 323 is provided with the lingers 22 and 29, between which the end oli the spring 3U is mounted, the other end titl Ell ot said spring engaging the head 39 oli the lever 38, as shown in Figure V civ the drawing. rllt will be apparent that, as this bimetallic strip deapands due to heat, it will swing as shown by dotted lines in lligurel, tilting the holder on its tule and moving the brush in a direction opposite to the' direction ot rotation ot the armature.

From the description ci the pa friven above, the operation ci? my device should be very rdily understood,

nettare ln higure lV lll have shown in lull lines the position of the brush' whichvv may be called the position of maximum output.

'lhat is, the position in which the'brush will be adjusted and designed to operate in the coldest weather, which is likely to obtain.

'llhe loi-metallic strip 26 may be adjusted on the bolt 25, so as to permit the brush to stand" in the position shown in full lines. lit will be apparent then, that, as the temperature adjacent the brush increases, the unequal expansion of the parts oi the loi-metallic strip 26 will cause the same to alter its position so that the tree end thereof will swing the brush on its tulcrum between the edges 2l oit they flanges, so as to tilt the brush and move it in a direction opposite to the direction ot rotation ofthe armature, thus decreasing the output ot the generator. As the temperature decreases, the loi-metallic strip will return to its first position and the spring 3l engaging the end of the brush will tend to return it to its-original position, so it will be seen that l have provided temperature controlled means tor positioning the third brush relative to the armature, so as tol shown in dotted lines in Figure V, so as to lll@ tilt the brush 22 on its iulcruin between the f edires of the dan es 3d.

am aware t at the particular embodiment of my invention, here shown andy described, is susceptible oit considerable variation without departing from the spirit ot my invention, but l have found that this particular vembodiment is desirable from \'many standpoints, and, therefore, li desire to claim the same specifically as well as broadly as indicated by the appended claims. Having thus-described' my invention, what ll claim as new and desire to secure by Letters Patent is- J i. lin a dynamo-electric machine having a contator, and a pair oit' inain brushes,

an adjustable third brush and temperature controlled means responsive to the' temperature oi said machine tor vary tion ot said third brush.

2. lin a olmo-electric machine having a mi utator, and a pair or ed main y brushes, a third brush, means whereby the position et mid third brush y be iw lly adiusted andsupplemental means controlledV n the pesiby temperature for adjusting Said third brush.

3. In a dynamo-electric machine having a commutator, a brush supporting device having a main brush, a third brush movably mounted on said deviceand temperature controlled means carried by said brush supporting device for moving said third brush relative to said main brush.

'l 4. In a dynamo-electric machine having a commutator, a member encirclin said commutator for supporting a plura ity of brushes, a third brush adjustably mounted on said member and temperature controlled means comprising a plurality of strips of different kinds oil metal carried by said member and co-operative with said third brush to adjust its position in response to changes in temperature in the vicinityA thereof.

5. In a d namo-elec'tric machine, the combination o a brush, a holder therefor and temperature responsive means for moving said brush in said holder.

6. In a dynamo-electric machine having a commutator, the combination of a brush, a holder therefor, resilient means. for pressin said brush against said commutator an temperature res nsive means for moving said brushiin said holder.

7. In a dynamo-electric machine having a,k

commutator, the combination of a brush, a holder therefor, a sprin carried by said holder for pressing said rush against said commutator and means responslve to the v temperature of the surroundin medium for moving said brush in said hpl er.

8. In a d name-electric machine, the combination ofya brush holder, a brush therein,

,temperature responsive means secured to said holder and engaging said brush to rock the same in said holder.

9. In a dynamo-electric machine, the combination of a brush, a holder therefor having means to permit a rocking movement thereof, a bi-metallic member secured to said holder and engaging said brush to rock said brush with changes 1n temperature.

combination of a brush, a holder therefor having means for loosely holding said brush, y f

a spring carried by said holder for pressing against said brush, and a bi-metallic member a so carried by said holder and engaging said brush to rock the same in response to changes in temperature of the surrounding medium. i

11. In a dynamo-electric machine,`having a commutator, a frame, a supporting rin surrounding said commutator, a pair o brush holders secured to saidl ring, main brushes carried by said holders, means for adjustably securing said ring to said frame to permit a rotative movement about said commutator, a third-brush holder carried by said ring, means permitting ad'ustment of said third-brush holder on sai ring, a third brush mounted in said third-brush holder to have a limited rocking movement, means for pressing said third brush against said commutator, and a bi-metallic strip carried by said third-'brush holder ,A and engaging said third brush for rocking the same in response to changes in temperature of the surrounding medium.

12. In a machine of the class described, the combination of a bracket; a third. brush carried thereby, so as to tilt relative thereto; temperature-controlled means carried by said bracket for tilting said thirdbrush; and

spring means .for returning said third brush to normal position.

13. In a machine of the class described, the combinationof a bracket; a third brush carried thereby, and fulcrumed therein; and temperature-controlled means carried by said bracket for rocking said third brush on its fulcrum. v

14. In a machine of the class described,

the combination of a third brush; a bracket 'carrying said third brush, said third brush being movable relative to said bracket; and heat-responsive means carried by said bracket for moving said third brush.

In testimony whereof I ailix my si ature.

ALVIN E. BUCHENB RG. 

